Cross-Cutting Concerns — quiz

A TestNG suite runs 50 tests in parallel across 5 threads. All tests share a static `WebDriver driver` field. Tests are failing randomly with `StaleElementReferenceException` and `NoSuchSessionException`. What is the root cause and fix?

• The tests are running too fast — add `Thread.sleep(2000)` before each `findElement` call
• A shared static `driver` field means all threads use the same browser session. Thread A's actions interfere with Thread B's driver state. Fix: use `ThreadLocal<WebDriver>` so each thread owns its own driver instance, isolated from other threads
• TestNG parallel execution is incompatible with Selenium WebDriver — switch to sequential execution
• The `StaleElementReferenceException` means the page objects need more robust XPath selectors